The Development of Amyloid β Protein Deposits in the Aged Brain

Abstract
The deposition of amyloid protein (A) in the human brain and the generation of neurofibrillary tangles are the histopathological hallmarks of Alzheimer's disease. Accumulation of A takes place in senile plaques and in cerebrovascular deposits as a result of an imbalance between A production and clearance. This Review describes the different types of A deposits, which can be distinguished by their morphology and by the hierarchical involvement of distinct areas of the brain in A deposition. The role of intracellular A in A deposition and the mechanism of A toxicity are also discussed.